Enhanced Variable Rate Codec (EVRC) is a speech codec used in code division for multiple access (CDMA) wireless telephone systems. EVRC is source controlled variable rate coder where the a frame of speech corresponding to 20 mS of speech can be encoded in any one of full rate (171 bits), half rate (80 bits) and one-eighth rate (16 bits) depending on the speech content. The coder has noise pre-processor (NPP) which suppresses background noise to improve the quality of speech. There is a need in the art to improve the noise pre-processor under noisy conditions to improve the speech quality.